Wednesday, May 21, 2008

It looks like an ordinary baseball cap. But when you put it on, the cap detects and analyzes the electroencephalogram (EEG) signals from your brain. It can even tell you if you’re getting too sleepy when driving based on your brain wave patterns.

As the researchers explain, by measuring EEG signals, the BCI system can monitor an individual’s physiological and cognitive states. The system takes advantage of advances in sensor and information technology to achieve reduced power consumption and production costs. Currently, the system can operate continuously for about two days before the lithium-ion battery needs to be recharged, but the researchers hope to further increase the lifetime.

The cap contains five embedded dry electrodes on the wearer’s forehead, and one electrode behind the left ear, that acquire EEG signals. Then, the EEG signals are wirelessly transmitted to a data receiver, where they are processed in real-time by a dual-core processor. The BCI system includes Bluetooth transmission for distances of 10m or less (e.g., for driving applications), as well as RF transmission for distances up to 600m (e.g., for potential sports applications). Next, the processed signals are transmitted back to the cap, where the data can be stored, displayed in real-time on a screen, or be used to trigger an audio warning, if necessary.